This invention relates to an apparatus for winding a multiplicity of threads onto respective bobbin tubes. More particularly, this invention relates to an apparatus on a winding machine for separating and threading up two threads supplied continuously at high speed towards two bobbin tubes.
Multiple-bobbin tube winders have been known, such as described in U.S. Pat. No. 3,880,371, wherein two thread packages are formed simultaneously on two bobbin tubes placed onto a common bobbin chuck, their face sides being adjacent. In order to perform a bobbin change with such a device, the threads are first severed and are inserted into a suction device held in the hand of an operator. Subsequently, the full bobbins are exchanged for empty bobbin tubes. In order to thread the two threads onto the empty bobbin tubes, the threads are threaded manually, using the suction device, into which the threads have been sucked during the bobbin change, through a slot-shaped thread guide in a downward direction and into contact with the two empty bobbin tubes and are taken up together by the bobbin tubes in the zone where the tubes are joined. The zone where the bobbin tubes are joined is provided with a circumferential recess for taking up the waste windings. After the threads are taken up in the recess, and after a number of waste windings are formed, the threads are released by retracting the slot-shaped thread guide. Due to the thread tension components directed towards the respective bobbin tube centers, the threads move towards the right and left of the recess to the respective winding zones, a few spiral windings being placed onto the bobbin tube.
However, this known device has disadvantages which preclude the use of automatic bobbin change devices (doffers). One of these disadvantages resides in the need for a manual severing of the incoming threads before sucking them off, as well as in the subsequent manual threading of the threads into the thread guide and placement into a common circumferential groove on the bobbin tubes. The threading in process of the two threads at the middle of both tubes also results in the production of two different bobbin packages, namely, a left hand one and a right hand one. Differing bobbin packages, however, are not desirable in further processing.
Accordingly, it is an objective of the invention to create a reliable and simple device requiring a minimum of suction air for separating and threading-in threads in changing the bobbin packages on a double winding position.
It is another object of the invention to provide an apparatus which can be used with automatic bobbin change devices to wind a plurality of threads onto separate bobbin tubes.
It is another object of the invention to reduce the air consumption required for holding severed thread ends in a multiple-bobbin tube winder.
It is another object of the invention to wind bobbin packages of the same type on a multiple-bobbin tube winder.
It is another object of the invention to provide a multiple-bobbin tube winder which can be operated at least semi-automatically with a minimum of manual labor.
Briefly, the invention provides an apparatus for winding a multiplicity of threads onto respective bobbin tubes. The apparatus includes a common bobbin chuck for receiving a multiplicity of bobbin tubes for example two, a common package drive for driving the chuck, a movable thread severing means to sever the threads supplied to the bobbin tubes and a movable common thread suction means for moving with the severing means to draw in the severed ends of the threads. In addition, the apparatus includes a plurality of pairs of thread holders with each pair being positioned at a respective bobbin tube. One holder of each pair is movable from a first position located out of the path of a respective thread to a second position to move the respective thread into the other holder of the pair and onto a respective bobbin tube.
The apparatus also includes a plurality of thread transversing guides, each of which is positioned adjacent a respective bobbin tube as well as a plurality of reserve winding devices, each of which is positioned adjacent a respective bobbin tube. The movable thread holder upon moving back to the initial position, allows each thread to move into a respective reserve winding device and traversing guide.
The severing means may be in the form of a knife while the suction means is in the form of a tube on which the knife is mounted. In this arrangement, both the knife and tube move in parallel relation with the bobbin chuck to sever and draw on the threads at the start of a bobbin change.